I've taken on a technical challenge and asking the audience if there is experience "out there" to help.

I am prototyping very small two layer stretch gortex tubes. The tubes will be about 1.5" long and only 3/8th" in diameter. If I fold the gortex over, sew it or (???) and seam seal it is that the best way to get what I want?

Because I only need the "tube" to stretch in circumference it is less important that seam sealing will reduce the stretch abilities of the Gortex.